I actually found an old pm where I asked him this a long time ago. Here's his Response:

Jacket should *PROBABLY* have "Fox Video" logo at at the bottom.
(Older ones said "CBS/FOX".) Auction photo looks correct.

Inner sleeves should *PROBABLY* be of 2-ply construction:
paper on the outside with polythene lining.

To be certain, you must ask the seller to check the mint markings.
See examples there:
http://www.blamld.com/LaserDisc/Technidisc.htm
Look for the name Technidisc with an icon resembling a CRT screen
etched into the 'dead wax'

I guess there is not a good way to know since they are unopened.